Cigarette rod cut-off device with knife adjustable about three axes



July 14, 1964 R wLANDs ETAL ADJUSTABLE ABOUT THREE AXES Filed NOV. l0, 1960 Figi T.O CIGARETTE ROD CUT-OFF DEVICE WITH KNIFE 4 Sheets-Sheet 1 /IVVE/VTORS TOI Rowmuos nm, JRHES Mlfhul Mnsau WNBA. Cult, G RINDLE qbJHSON July 14, 1964 T. RowLANDs ETAL 3,140,632

CIGARETTE ROD CUT-OFF' DEVICE WITH KNIFE ADJUSTABLE ABOUT THREE AXES Filed Nov. lO, 1960 4 Sheets-Sheet 2 pag.2.

/A/Vf/VWRS Tom Romanos wb Jamas m-rnvk Mksaw July 14, 1964 T. RowLANDs ETAL 3,140,632

CIGARETTE ROD CUT-OFF DEVICE WITH KNIFE v ADJUSTABLE ABOUT THREE AxEs 4 Sheets-Sheell 3 Filed Nov. lO, 1960 /NVENTORS Tom Rowman nnb James #mmm mnsvu BY H0150, calf, mane 1. uns',

July 14, 1954 T. RowLANDs ETAL 3,140,632

CIGARETTE Ron CUT-OEE DEVICE wITH KNIFE ADJUSTABLE ABOUT THREE AxEs Filed Nov. l0, 1960 4 Sheets-Sheet 4 l/VVE/VTRS Tom Romanos Aub JBMSS Gamuz www wmsw, Calf, G mme 1- wnsm United States Patent O 3,140,632 CIGARETTE R01) CUT-OFF DEVICE WITH KNIFE ADJUSTABLE ABOUT THREE AXES Tom Rowlands and James Arthur Mason, London, England, assignors to Molins Machine Company Limited, Deptford, London, England, a British company Filed Nov. 10, 1960, Ser. No. 68,559 Claims priority, application Great Britain Nov. 13, 1959 Claims. (Cl. 83-310) This invention relates to devices such as are used in continuous rod cigarette-making machines to sever the cigarette rod into cigarette lengths, or multiples of such lengths. Such a device will be referred to hereinafter as a cut-off. These cut-oifs are also used in continuous rod machines for making short lengths of stub material for use as filters for cigarettes, and the expression rod where used herein shall, where the context permits, be understood as including a continuous rod of stub material as well as a cigarette rod.

According to the present invention there is provided a cut-off comprising, in combination, a knife having a helical blade of progressively increasing radius (eg. a spiral) skewed with respect to the rod to sever the rod, perpendicularly to the axis of the rod, on rotation of the knife about the axis of generation of the helix; and a ledger for supporting the rod during cutting and extending circumferentially around at least half of the periphery of the rod, the ledger being arranged for reciprocation along the axis of the rod in timed relation with the rotation of the knife, the angular extent of the blade and the motion of the ledger being chosen in relation to each other so that the ledger travels at substantially the speed of the rod while the rod is being cut.

Further according to the present invention, there is provided a cut-off comprising, a knife having a helical blade of progressively increasing radius (eg. a spiral) skewed with respect to the rod to sever the rod, perpendicularly to the axis of the rod, on rotation of the knife about the axis of generation of the helix, a ledger to support the rod during cutting and extending circumferentially around at least half of the periphery of the rod, and a crank mechanism driven in phase with rotation of the knife, and having a connecting rod pivotally mounted at one end on the crank mechanism, and at its other end on the ledger, to reciprocate the ledger, the crank mechanism being arranged relatively to the pivot point on the ledger such that the axis of the connecting rod passes through parallelism with the cigarette rod during cutting of the cigarette rod and when said one end of the connecting rod on the crank mechanism is at its nearest position to the cigarette rod path, the angular extent of the cutting portion of the blade not exceeding 24 on either side of said position of parallelism.

Further according to the present invention there is provided a cut-off for a continuous rod cigarette-making machine, comprising a member mounted for rotation about an axis skewed with respect to the axis of the rod, and carrying a knife having a blade extending helically and of progressively increasing radius (eg. a spiral and arranged to cut the rod on rotation of the rotatable member, the rotatable member being arranged for angular adjustment about an axis perpendicular to its rotational axis and to the axis of the rod, and the knife being arranged for angular adjustment in a plane parallel with the axis of rotation so that the rod is severed perpendicularly thereto.

By angular adjustment of the rotatable member and the knife, the cut-off can be adjusted to cut cigarette lengths varying slightly from the cigarette length corresponding to the pitch of the helix of the blade. For example, one knife could be arranged to cut cigarette lengths iCC Patented July 14., 1964 varying between 70 mm. and 73 mm. Alternatively, or if a markedly different cigarette length is to be cut, the knife could be replaced by one having a blade with a pitch corresponding to the new cigarette length.

The rotatable member may be arranged for angular adjustment about an axis perpendicular to the axis of the said member, and to the axis of the rod, by being mounted for rotation about a shaft journalled in a part-cylindrical member having its axis coincident with the axis about which adjustment is to be made, the part-cylindrical member being angularly adjustable in a part-cylindrical recess in supporting structure.

The knife may be arranged for angular adjustment by being mounted on a carrier having a iiat base which is secured on a flat surface on the rotatable member, and parallel with its axis of rotation, by means of cooperating threaded members (eg. nuts and bolts). The knife may be arranged to pivot about an axis perpendicular to the flat surface and adjacent its leading edge.

The blade of the knife may be made of a material having a high resistance to wear, e.g. tungsten carbide.

The ledger for supporting the rod while it is being cut by the knife may comprise two aligned tubular portions through which the rod passes with a small clearance and which are spaced apart sufficiently for the blade of the knife to pass therebetween, the ledger being reciprocated in the direction of the rod axis (eg. the ledger may be mounted on long spring blades and reciprocated by a crank mechanism) so that the ledger speed is equal to, or substantially equal to, the speed of the rod during cutting.

One example of a cut-off according to the present in vention will now be described, by way of example, with reference to the drawings:

FIGURE 1 is a front elevation of the cut-olf showing the cigarette rod, knife and ledger;

FIGURE 2 is a view corresponding to FIGURE 1 and partly in section to show the driving arrangements, the cigarette rod and the ledger being removed;

FIGURE 3 is a view taken on the line 3-3 of FIGURE 2; and

FIGURE 4 is a view of the knife and the ledger taken in the direction of arrow A in FIGURE l.

Referring first to FIGURE l, a portion of the continuous cigarette rod is shown at CR moving in the direction of the arrows and passing through the ledger it) which comprises an entry portion 11 with a funnel-shaped interior and two portions 12 and 13 with cylindrical interiors through which the rod passes with a small clear* ance and which are spaced from each other by a small gap through which the blade of the cigarette knife passes to sever the rod. The cigarette which is being severed from the rod is shown at C.

The ledger 10 is mounted on a block 14 which in turn is carried on the ends of two long flat spring blades 15 which are mounted at their other ends on a block 16 secured to stationary structure.

The block 14 has a pin 17 extending therefrom which is pivotally embraced by one end of a connecting rod 18 operated by a crank mechanism 19 which will be described later.

The cigarette rod is severed by means of a knife 20 which is mounted on a disc 21 (FIGURES l, 2 and 4). The knife 2t! comprises a blade 22 of tungsten carbide and a carrier 23 to which it is secured by three setscrews 24. The carrier 23 has a flat base 25 and is secured on a flat surface 26 on the disc 21 by means of two nuts and bolts 27, 28, two apertures 29 being provided in the disc 21 for reception of the nuts. The bolt 27 passes through a cylindrical hole 30 and the bolt 21 passes through a slot 31 in the disc 21 so that the carrier 23 can be pivoted about the axis of the bolt 27 and parallel with the surface 26.

The disc 21 has a circular recess 32 by means of which the disc is fitted on to a disc 33 on the end of a shaft 34. Arcuate slots 35 (see FIGURE 4) are provided in the disc 21 through which setscrews 36 pass to secure the disc 21 on to the disc 33 in a manner permitting relative angular adjustment` The shaft 34 is arranged to drive the disc 21 in a manner to be described later.

The shaft 34 is journalled in a part-cylindrical member 37 which has a circular base 38 (FIGURES 2 and 3), the axis of the member 37 passing through the center of the blade 22 and being perpendicular to both the axis of the cigarette rod and the axis of shaft 34. The partcylindrical member 37 is received in a part-cylindrical recess formed by curved portions 39, 40 of wall 41 which forms part of the main structural support of the cut-off.

A bracket 42 is provided adjacent the circular base 38 of member 37 and has a hollow boss 43 in which is journalled a stub shaft 44 which is secured in the center of circular base 38, the bracket also comprising a circular faceplate 45 against which bears the circular base 38 The disc 21 is therefore angularly adjustable about the axis of the part-cylindrical member 37 by rotation of the member 37 about the stub shaft 44. To clamp the member 37 in position, four setscrews 46 are provided, which pass through slots 47 in the member 37 and are threaded into the curved portions 39, 40 of wall 41, and four setscrews 48 are provided which pass through arcuate slots 49 in the circular faceplate 45 and are threaded into the circular base 38.

The driving arrangements for the disc 21 and the crank mechanism 19 will now be described (FIGURES 2 and 3).

A main shaft 50 is journalled for rotation in walls 51 and 41 of gear box 52. An input drive gear wheel 53 is secured to the shaft 50 to be driven from the main drive of the cigarette-making machine with which the cut-off is being used. A helically-toothed gear wheel 54 is keyed to shaft 50 and meshes with a helically-toothed gear wheel 55 which is integral with a similar gear wheel 56. Gear wheel 56 in turn meshes with a further helical gear wheel 57 which is keyed to the shaft 34.

At its left-hand end the shaft 34 is mounted in a ball race 58 which is carried by the left-hand end of a rectangular box 59, the right-hand end of the box being secured by setscrews (not shown) to the part-cylindrical member 37. The box 59 is open at its side 60 to permit meshing of the gear wheels 56 and 57.

The gear wheels 55 and 56 are arranged to rotate about an axis parallel to the axis of the part-cylindrical member 37, i.e. parallel to the axis about which the disc 21 is angularly adjustable, and perpendicular to the plane in which the axis of shaft 34 moves on such adjustment, and the axis of shaft 50 is arranged in a plane parallel with the latter plane.

To maintain gear wheels 54 and 56 in mesh respectively with gear wheels 55 and 57, while allowing angular adjustment of part-cylindrical member 37, the gear wheels 55 and 56 are mounted for rotation on a shaft 61 which is mounted at its ends in a generally U-shaped carrier 62. The ends 63 of the carrier are formed as clamps which are tightened, by means of setscrews 64, on to the ends of the shaft 61. Two plates 65 are secured by grubscrews 66 to the ends of the clamps 63 and these plates 65 each have secured thereto an externally threaded tube 67 which is in threaded engagement with one of a pair of threaded bores 68 in the clamps 63. In line with each bore 68 is a bore 69 of smaller diameter and a bore 70 of intermediate diameter is provided in each end of the shaft 61. At each end of the carrier 62 a stationary rod 71 passes through the bores 69 and 70 and into the interior of the tube 67 in which it is a sliding tit to be supported thereby. The rods 71 are also a sliding t in the bores 69. The other ends of the rods 71 are a tight tit in apertures 72 formed in bosses 73 in wall portion 40. The tubes 67 are supported for rotation in a plate 74 and a plate 75 which are secured to wall 51 in a manner not shown. The carrier 62 is thus supported on the tubes 67 and the rods 71.

A nut 76 carrying a toothed sprocket 77 is provided on each tube 67 between the plates 74 and 75, and a chain 78 passes around the two sprockets 77 and around a sprocket 79 mounted on a shaft Si) which is journalled in plate 75 and has a knurled operating wheel 81. Thus, by rotation of the knurled wheel 81, the nuts 76 are rotated and the tubes 67 are moved in or out of the gear box 52, carrying with them the carrier 62 and the gear wheels 55 and 56. The rods 71 and tubes 67 are arranged in a plane parallel to the axis of shaft 5t) so that gear wheels 54 and 55 remain constantly and correctly in mesh. As will be seen, at a given angular position of shaft 34 such movement of gear wheel 56 will alter the depth of engagement of the gear wheels 56 and 57 so that for each such angular position of shaft 34 the gear wheels 55 and 56 can be moved to a position in which the gear wheel 56 is correctly in mesh with the gear Wheel 57.

The crank mechanism 19 (FIGURE 3) is driven from the shaft 56 by means of a bevel gear wheel 82 (FIGURE 2) mounted on the shaft 51') which drives a further bevel gear wheel 83 (FIGURE 3) mounted on a shaft 84 at right angles to shaft Si). The shaft 84 is mounted in bearings 85 secured in a tube-like portion 86 of casing 87 of the crank mechanism 19 which extends into the interior of the gear box 52. At its other end the shaft 84 carries a spur gear wheel 88 which drives a spur gear wheel 89 mounted on a shaft 90 which is journalled in the casing 87. At its other end the shaft 90 carries an eccentric 91, the pin 92 of which is rotatably mounted in the connecting rod 18. The rotational speed of the eccentric 91 is equal to that of the disc 21 but the speed of the pin 92 in its circular path is arranged to be slightly greater than the speed of the cigarette rod. A different eccentric 91 is therefore provided for each cigarette length, or the pin 92 may be made adjustable to provide paths of different diameters.

During adjustment of the angular position of disc 21 and shaft 34 it is probable that relative angular movement will occur between the gear wheels 54 and 57. As the position of the ledger 10 is dependent on the angular position of shaft 50, and the position of the knife 20 depends on the angular position of disc 21 about its axis of rotation, the slots 35 in the disc 21 are provided to allow angular adjustment of disc 21 relative to shaft 34 about the rotational axis to restore the knife 20 and ledger 10 to their correct relative positions.

The cut-off is operated in the following manner. The speed of the input gear wheel 53 is adjusted (c g. by changing the speed ratio of the drive (not shown) from the cigarette machine to the gear wheel 53). The eccentric 91 appropriate to the cigarette length is incorporated. A blade 22 appropriate for the length of cigarette to be produced is secured in the carrier 23 by the setscrews 24 and the carrier 23 is secured to the disc 21 by the nuts and bolts 27 and 28 which are tightened only sufficiently to allow pivotal movement of the carrier 23 about the axis of bolt 27. The blade 22 may be such that its pitch normal to the helix, i.e., the distance any point on the blade edge travels in a direction perpendicular to the blade edge at that point during one revolution of the disc 21 is equal to, or approximately equal to, the cigarette length. The former would probably be the case if the cigarette length is standard, whereas the latter would probably be the case if the cigarette length is non-standard and a relatively small quantity of cigarettes are to be made, so that it may not be worth making a new blade 22. For example one blade may be used for lengths between 70 mm. and 73 mm.

The setscrews 46 and 48 are slackened and the part- Cylindrical member 37 is rotated about stub shaft 44 until the axis of shaft 34 is skewed with respect to the cigarette rod at the appropriate angle. A Vernier scale may be provided, for example, on the circular base 38 and circular faceplate 45 to facilitate this adjustment. The setscrews 46 and 48 are then tightened.

The knurled wheel 81 is rotated to bring gear wheels 56 and 57 correctly into mesh and setscrews 36 are slackened to allow relative angular adjustment of disc 21 with respect to disc 33 so that the knife blade 22 will pass through the gap between portions 12 and 13 of the ledger on rotation of shaft 34, and the nuts and bolts 27 and 2S are tightened when the blade 22 passes through the ledger gap with a nominal working clearance on either side.

It is arranged that the angular extent of the cutting edge of the blade 22 is 40 in this embodiment. The blade enters the ledger 10 when the eccentric pin 92 is 20 before its top dead center, i.e. before the position shown in FIGURE l at which it is at its nearest point to the path of the cigarette rod CR, and leaves 20 after top dead center. At top dead center the connecting rod 18 is substantially parallel with the path of the cigarette rod and the speed of the ledger is therefore the speed of the eccentric pin. The diameter of the path of the eccentric pin is chosen so that the speed of the pin is slightly greater than the speed of the cigarette rod (and thus of the blade 22 in the direction of travel of the rod) and so that at the point at which the blade enters the ledger, the ledger is travelling instantaneously at cigarette rod speed. For the first 20 of the cut the ledger accelerates, and for the second 20 it decelerates, and its speed is therefore greater than cigarette rod speed during the cut, except at the instant of entry and exit. The ledger therefore moves forward relative to the blade, which enters the ledger gap at the forward end and leaves at the rearward end. If the cut be extended to 24 on either side of top dead centre the blade will enter the ledger gap at the rearward end and move (relative to the ledger) to the forward end of the gap during the rst 4.. Similarly, in the last 4 the ledger will move backwards and the blade will leave the gap from the forward end. Thus three traversals of the ledger gap will be made during cutting. u

The ledger gap must be as small as possible so that the rod is adequtaely supported during cutting. However, due to the brittle nature of tunsten carbide the blade must not contact the ledger. Thus the ledger gap must be large enough to allow for relative movement along the axis of the cigarette rod between the ledger and the blade when, as in the present embodiment, the ledger does not travel at constant velocity during the cut. l

It has been found that, with a simple crank mechanism as described, by arranging for the connecting rod to pass through parallelism with the path of the cigarette rod when the eccentric pin is at its nearest point to this path during the cut, a cut of angular extent of up to 40 (or up to 48 if three traversals of the ledger gap are made by the blade as described above) can be obtained with a relative movement of the blade in the gap which has a negligible effect on the quality of the cut. This .angle allows for a long slicing cut without excessive rubbing of the severed ends of the rod.

In addition a nominal working clearance is allowed for between the blade and the ledger at each side of the gap.

The use of tungsten carbide as the blade material reduces or may even avoid any need for regrinding of the blade edge in situ, but it may be desirable for the blade edge to be honed in situ.

The adjustments described permit different cigarette lengths to be cut either by replacing the blade 22 and by angular adjustment of disc 21 about the stub shaft 44 and adjustment of the knife carrier 23 on the surface 26 of disc 2.1 or by making the latter adjustments if the cigarette length is approximately equal to the pitch of the helix normal to the helix angle. Adjustment of the knurled wheel S1 restores correct mesh to the driving arrangements and angular adjustment of disc 21 relative to disc 33 brings the knife 20 back into phase with reciprocation of the ledger 10.

What we claim as our invention and desire to secure by Letters Patent is:

l. A cut-off for a continuous rod cigarette-making machine comprising a helical knife for cutting-olf cigarette lengths from a continuous cigarette rod, the helical knife having a sickle edge, a rotatable knife-carrying member, a driving shaft carrying the knife-carrying member, means detachably and adjustably mounting said knife on said member to permit replacement of the knife and its adjustment in a plane parallel with the axis of rotation of the member and over a small range about and including the position at which the knife is a helix about the axis of rotation of the member, so that the knife is at least substantially a helix about the axis of rotation of the member, stationary structure, means rotatably mounting the driving shaft of said knife-carrying member in said stationary structure for angular adjustment of its rotational axis about an axis mutually perpendicular to the rotational axis and the cigarette rod at the point of cutting, to bring the knife into a position at which the cigarette rod is cut at right angles, whereby different cigarette length can be cut off by utilising a knife of appropirate helix and making the adjustments.

2. A cut-off as claimed in claim l wherein the stationary structure comprises means defining a part-cylindrical recess, and the means rotatably mounting the driving shaft of said knife carrying member for angular adjustment of its rotational axis comprises a part-cylindrical sleeve angularly adjustable in the part-cylindrical recess, the axis of the sleeve being mutually perpendicular to the rotational axis and the cigarette rod at the point of cutting, and means rotatably mounting said driving shaft in said part cylindrical sleeve.

3. A cut-off as claimed in claim l and comprising a knife carrier with a flat base, means mounting said knife on said knife carrier, the rotatable knife-carrying member having a at surface parallel with its axis of rotation, the means detachably and adjustably mounting said knife on the knife-carrying member comprising cooperating threaded members to secure the knife carrier in position on the fiat surface of the knife-carrying member.

4. A cut-off as claimed in claim l and comprising a ledger for supporting the cigarette rod while it is being cut, the ledger comprising two aligned tubular members through which the rod passes and spaced apart by a gap for the knife to pass therebetween, a crank mechanism, means to drive said crank mechanism in phase with rotation of the knife, a connecting rod pivotally mounted at one end on the crank mechanism and pivotally mounted at its other end on the ledger to reciprocate the ledger, the crank mechanism being at such a location relative to the ledger that the connecting rod is parallel with the cigarette rod at the mid-point of the cutting of the cigarette rod by the knife, the peripheral speed of the pivot point of the connecting rod on the crank mechanism being greater than the speed of the cigarette rod by such an amount that the speed of the ledger at the beginning and end of the cutting of the rod when the knife respectively enters and leaves the ledger is equal to the speed of the cigarette rod, the gap between the two aligned tubular members of the ledger being large enough to accommodate the movement of the ledger relative to the knife and cigarette rod during cutting of the rod.

5. A cut-off as claimed in claim 4 and comprising two parallel spring blades to support the ledger, the ledger being mounted on adjacent ends of the spring blades and the other ends of the spring blades being mounted on stationary structure.

(References on following page) References Cited in the le of this patent UNITED STATES PATENTS Bradshaw Nov. 30, 1915 Weisner Oct. 7, 1924 Molins Feb. 24, 1931 Molins et al. Apr. 14, 1931 Ruau Mar. 15, 1932 Rundell Nov. 27, 1932 Hohn Jan. 3, 1933 Brandt Nov. 7, 1933 Jensen et al. Feb. 1, 1938 Comstock Feb. 22, 1938 Hamel June 18, 1940 Rudert et al. Oct. 19, 1943 James Sept. 13, 1955 Morgan Apr. 14, 1959 Segal Nov. 1, 1960 

1. A CUT-OFF FOR A CONTINUOUS ROD CIGARETTE-MAKING MACHINE COMPRISING A HELICAL KNIFE FOR CUTTING-OFF CIGARETTE LENGTHS FROM A CONTINUOUS CIGARETTE ROD, THE HELICAL KNIFE HAVING A SICKLE EDGE, A ROTATABLE KNIFE-CARRYING MEMBER, A DRIVING SHAFT CARRYING THE KNIFE-CARRYING MEMBER, MEANS DETACHABLY AND ADJUSTABLY MOUNTING SAID KNIFE ON SAID MEMBER TO PERMIT REPLACEMENT OF THE KNIFE AND ITS ADJUSTMENT IN A PLANE PARALLEL WITH THE AXIS OF ROTATION OF THE MEMBER AND OVER A SMALL RANGE ABOUT AND INCLUDING THE POSITION AT WHICH THE KNIFE IS A HELIX ABOUT THE AXIS OF ROTATION OF THE MEMBER, SO THAT THE KNIFE IS AT LEAST SUBSTANTIALLY A HELIX ABOUT THE AXIS OF ROTATION OF THE MEMBER, STATIONARY STRUCTURE, MEANS ROTATABLY MOUNTING THE DRIVING SHAFT OF SAID KNIFE-CARRYING MEMBER IN SAID STATIONARY STRUCTURE FOR ANGULAR ADJUSTMENT OF ITS ROTATIONAL AXIS ABOUT AN AXIS MUTUALLY PERPENDICULAR TO THE ROTATIONAL AXIS AND THE CIGARETTE ROD AT THE POINT OF CUTTING, TO BRING THE KNIFE INTO A POSITION AT WHICH THE CIGARETTE ROD IS CUT AT RIGHT ANGLES, WHEREBY DIFFERENT CIGARETTE LENGTH CAN BE CUT OFF BY UTILISING A KNIFE OF APPROPIRATE HELIX AND MAKING THE ADJUSTMENTS. 